蝴蝶兰不同品种表型性状遗传多样性分析

以72份蝴蝶兰品种为研究对象，对其叶片、花梗和花器官相关的34个表型性状进行测定与评价，通过表型多样性分析、聚类分析和主成分分析等方法，探讨其种质资源表型性状的遗传多样性。结果表明：72份蝴蝶兰品种的绝大多数性状呈现变异丰富、类型多样的特性，数量性状遗传多样性变异范围为16.39%～157.36%，质量性状Shannon−Wiener多样性指数范围为0.38～1.32，其中叶片的数量性状变异程度较低，但其质量性状的多样性水平较高；R型聚类分析将34个性状分为3个大类，第I类群包含了花部和叶部性状，表明花与叶的表型联系较紧密，第II类群和第III类群包含花序长、最长叶长、植株大小和花序梗长，表明这4个表型性状呈独自进化关系； Q型聚类分析将72份蝴蝶兰种质资源分为4大类，其中第II类可细分为7个亚类群，II−1、II−2亚类群可作为大花和中花育种的亲本，II−3、II−4、II−5和II−7亚类群可作为小花育种的亲本，II−4亚类群可作为香花育种的亲本，同时蝴蝶兰‘JB5342’‘JB5184’‘JB5541’‘JB3697’‘安娜’和‘JB5725’等品种与多数供试蝴蝶兰品种遗传距离较远，可作为重要亲本参考。主成分分析表明，花宽、花瓣长、花瓣宽、萼片长、花长和萼片宽的特征向量绝对值较高，是造成蝴蝶兰表型变异的主要因素。

Analysis of Phenotypic Genetic Diversity of Various Phalaenopsis Varieties

In this study, 34 phenotypic traits involving leaves, floriferous shoot and floral organs of 72 Phalaenopsis germplasm resources were measured and evaluated by using means of phenotypic diversity analysis, principal component analysis and cluster analysis, the genetic diversity of germplasm phenotypic traits was explored. The results showed that the majority traits in 72 Phalaenopsis varieties had exhibited high degree of variation and rich types, the variation of quantitative traits was 16.39%–157.36%, and the Shannon-Wiener diversity index of qualitative traits was 0.38–1.32, the coefficient of variation of quantitative traits for leaf-related traits was small and stable, but the level of diversity of quality traits for leaf-related traits was relatively high. R-type cluster analysis divided the 34 traits into 3 clusters, with cluster I containing phenotypic traits of flower and leaf, indicating a close relationship between the phenotypes of flower and leaf, and clusters II and III only contained inflorescence length, longest leaf length, plant size and peduncle length, it is indicated that these 4 phenotypic traits including inflorescence length have the relationship for independent evolutionary. Q-clustering analysis divided the species of Phalaenopsis into 4 primary groups, group II could be subdivided into 7 subgroups. The germplasm of subgroups II−1 and II−2 could provide parental choices for large-flowered and medium-flowered breeding, the germplasm of subgroups II−3, II−4, II−5 and II−7 could provide parental choices for small-flowered breeding, the germplasm of subgroup II−4 could provide parental choices for fragrant-flowered Phalaenopsis breeding, and the genetic distances of 'JB5342', 'JB5184', 'JB5541', 'JB3697', 'Anna' and 'JB5725' were far with the most samples, and they could be selected as the significant hybrid parents. Principal component analysis showed that flower width, petal length, petal width, sepal length, flower length, and sepal width had high absolute value of eigenvector and were the main factors causing the phenotypic variation of Phalaenopsis.